include/dba.php

   1 <?php
   2
   3 use Friendica\Core\L10n;
   4 use Friendica\Core\System;
   5 use Friendica\Database\DBM;
   6 use Friendica\Database\DBStructure;
   7 use Friendica\Util\Temporal;
   8
   9 require_once('include/datetime.php');
  10
  11 /**
  12  * @class MySQL database class
  13  *
  14  * This class is for the low level database stuff that does driver specific things.
  15  */
  16
  17 class dba {
  18         public static $connected = true;
  19
  20         private static $_server_info = '';
  21         private static $db;
  22         private static $driver;
  23         private static $error = false;
  24         private static $errorno = 0;
  25         private static $affected_rows = 0;
  26         private static $in_transaction = false;
  27         private static $relation = [];
  28
  29         public static function connect($serveraddr, $user, $pass, $db, $install = false) {
  30                 if (!is_null(self::$db)) {
  31                         return true;
  32                 }
  33
  34                 $a = get_app();
  35
  36                 $stamp1 = microtime(true);
  37
  38                 $serveraddr = trim($serveraddr);
  39
  40                 $serverdata = explode(':', $serveraddr);
  41                 $server = $serverdata[0];
  42
  43                 if (count($serverdata) > 1) {
  44                         $port = trim($serverdata[1]);
  45                 }
  46
  47                 $server = trim($server);
  48                 $user = trim($user);
  49                 $pass = trim($pass);
  50                 $db = trim($db);
  51
  52                 if (!(strlen($server) && strlen($user))) {
  53                         self::$connected = false;
  54                         self::$db = null;
  55                         return false;
  56                 }
  57
  58                 if ($install) {
  59                         if (strlen($server) && ($server !== 'localhost') && ($server !== '127.0.0.1')) {
  60                                 if (! dns_get_record($server, DNS_A + DNS_CNAME + DNS_PTR)) {
  61                                         self::$error = L10n::t('Cannot locate DNS info for database server \'%s\'', $server);
  62                                         self::$connected = false;
  63                                         self::$db = null;
  64                                         return false;
  65                                 }
  66                         }
  67                 }
  68
  69                 if (class_exists('\PDO') && in_array('mysql', PDO::getAvailableDrivers())) {
  70                         self::$driver = 'pdo';
  71                         $connect = "mysql:host=".$server.";dbname=".$db;
  72
  73                         if (isset($port)) {
  74                                 $connect .= ";port=".$port;
  75                         }
  76
  77                         if (isset($a->config["system"]["db_charset"])) {
  78                                 $connect .= ";charset=".$a->config["system"]["db_charset"];
  79                         }
  80                         try {
  81                                 self::$db = @new PDO($connect, $user, $pass);
  82                                 self::$connected = true;
  83                         } catch (PDOException $e) {
  84                                 self::$connected = false;
  85                         }
  86                 }
  87
  88                 if (!self::$connected && class_exists('mysqli')) {
  89                         self::$driver = 'mysqli';
  90                         self::$db = @new mysqli($server, $user, $pass, $db, $port);
  91                         if (!mysqli_connect_errno()) {
  92                                 self::$connected = true;
  93
  94                                 if (isset($a->config["system"]["db_charset"])) {
  95                                         self::$db->set_charset($a->config["system"]["db_charset"]);
  96                                 }
  97                         }
  98                 }
  99
 100                 // No suitable SQL driver was found.
 101                 if (!self::$connected) {
 102                         self::$db = null;
 103                         if (!$install) {
 104                                 System::unavailable();
 105                         }
 106                 }
 107                 $a->save_timestamp($stamp1, "network");
 108
 109                 return true;
 110         }
 111
 112         /**
 113          * @brief Returns the MySQL server version string
 114          *
 115          * This function discriminate between the deprecated mysql API and the current
 116          * object-oriented mysqli API. Example of returned string: 5.5.46-0+deb8u1
 117          *
 118          * @return string
 119          */
 120         public static function server_info() {
 121                 if (self::$_server_info == '') {
 122                         switch (self::$driver) {
 123                                 case 'pdo':
 124                                         self::$_server_info = self::$db->getAttribute(PDO::ATTR_SERVER_VERSION);
 125                                         break;
 126                                 case 'mysqli':
 127                                         self::$_server_info = self::$db->server_info;
 128                                         break;
 129                         }
 130                 }
 131                 return self::$_server_info;
 132         }
 133
 134         /**
 135          * @brief Returns the selected database name
 136          *
 137          * @return string
 138          */
 139         public static function database_name() {
 140                 $ret = self::p("SELECT DATABASE() AS `db`");
 141                 $data = self::inArray($ret);
 142                 return $data[0]['db'];
 143         }
 144
 145         /**
 146          * @brief Analyze a database query and log this if some conditions are met.
 147          *
 148          * @param string $query The database query that will be analyzed
 149          */
 150         private static function log_index($query) {
 151                 $a = get_app();
 152
 153                 if (empty($a->config["system"]["db_log_index"])) {
 154                         return;
 155                 }
 156
 157                 // Don't explain an explain statement
 158                 if (strtolower(substr($query, 0, 7)) == "explain") {
 159                         return;
 160                 }
 161
 162                 // Only do the explain on "select", "update" and "delete"
 163                 if (!in_array(strtolower(substr($query, 0, 6)), ["select", "update", "delete"])) {
 164                         return;
 165                 }
 166
 167                 $r = self::p("EXPLAIN ".$query);
 168                 if (!DBM::is_result($r)) {
 169                         return;
 170                 }
 171
 172                 $watchlist = explode(',', $a->config["system"]["db_log_index_watch"]);
 173                 $blacklist = explode(',', $a->config["system"]["db_log_index_blacklist"]);
 174
 175                 while ($row = dba::fetch($r)) {
 176                         if ((intval($a->config["system"]["db_loglimit_index"]) > 0)) {
 177                                 $log = (in_array($row['key'], $watchlist) &&
 178                                         ($row['rows'] >= intval($a->config["system"]["db_loglimit_index"])));
 179                         } else {
 180                                 $log = false;
 181                         }
 182
 183                         if ((intval($a->config["system"]["db_loglimit_index_high"]) > 0) && ($row['rows'] >= intval($a->config["system"]["db_loglimit_index_high"]))) {
 184                                 $log = true;
 185                         }
 186
 187                         if (in_array($row['key'], $blacklist) || ($row['key'] == "")) {
 188                                 $log = false;
 189                         }
 190
 191                         if ($log) {
 192                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 193                                 @file_put_contents($a->config["system"]["db_log_index"], Temporal::utcNow()."\t".
 194                                                 $row['key']."\t".$row['rows']."\t".$row['Extra']."\t".
 195                                                 basename($backtrace[1]["file"])."\t".
 196                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 197                                                 substr($query, 0, 2000)."\n", FILE_APPEND);
 198                         }
 199                 }
 200         }
 201
 202         public static function escape($str) {
 203                 switch (self::$driver) {
 204                         case 'pdo':
 205                                 return substr(@self::$db->quote($str, PDO::PARAM_STR), 1, -1);
 206                         case 'mysqli':
 207                                 return @self::$db->real_escape_string($str);
 208                 }
 209         }
 210
 211         public static function connected() {
 212                 $connected = false;
 213
 214                 switch (self::$driver) {
 215                         case 'pdo':
 216                                 $r = dba::p("SELECT 1");
 217                                 if (DBM::is_result($r)) {
 218                                         $row = dba::inArray($r);
 219                                         $connected = ($row[0]['1'] == '1');
 220                                 }
 221                                 break;
 222                         case 'mysqli':
 223                                 $connected = self::$db->ping();
 224                                 break;
 225                 }
 226                 return $connected;
 227         }
 228
 229         /**
 230          * @brief Replaces ANY_VALUE() function by MIN() function,
 231          *  if the database server does not support ANY_VALUE().
 232          *
 233          * Considerations for Standard SQL, or MySQL with ONLY_FULL_GROUP_BY (default since 5.7.5).
 234          * ANY_VALUE() is available from MySQL 5.7.5 https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html
 235          * A standard fall-back is to use MIN().
 236          *
 237          * @param string $sql An SQL string without the values
 238          * @return string The input SQL string modified if necessary.
 239          */
 240         public static function any_value_fallback($sql) {
 241                 $server_info = self::server_info();
 242                 if (version_compare($server_info, '5.7.5', '<') ||
 243                         (stripos($server_info, 'MariaDB') !== false)) {
 244                         $sql = str_ireplace('ANY_VALUE(', 'MIN(', $sql);
 245                 }
 246                 return $sql;
 247         }
 248
 249         /**
 250          * @brief beautifies the query - useful for "SHOW PROCESSLIST"
 251          *
 252          * This is safe when we bind the parameters later.
 253          * The parameter values aren't part of the SQL.
 254          *
 255          * @param string $sql An SQL string without the values
 256          * @return string The input SQL string modified if necessary.
 257          */
 258         public static function clean_query($sql) {
 259                 $search = ["\t", "\n", "\r", "  "];
 260                 $replace = [' ', ' ', ' ', ' '];
 261                 do {
 262                         $oldsql = $sql;
 263                         $sql = str_replace($search, $replace, $sql);
 264                 } while ($oldsql != $sql);
 265
 266                 return $sql;
 267         }
 268
 269
 270         /**
 271          * @brief Replaces the ? placeholders with the parameters in the $args array
 272          *
 273          * @param string $sql SQL query
 274          * @param array $args The parameters that are to replace the ? placeholders
 275          * @return string The replaced SQL query
 276          */
 277         private static function replace_parameters($sql, $args) {
 278                 $offset = 0;
 279                 foreach ($args AS $param => $value) {
 280                         if (is_int($args[$param]) || is_float($args[$param])) {
 281                                 $replace = intval($args[$param]);
 282                         } else {
 283                                 $replace = "'".self::escape($args[$param])."'";
 284                         }
 285
 286                         $pos = strpos($sql, '?', $offset);
 287                         if ($pos !== false) {
 288                                 $sql = substr_replace($sql, $replace, $pos, 1);
 289                         }
 290                         $offset = $pos + strlen($replace);
 291                 }
 292                 return $sql;
 293         }
 294
 295         /**
 296          * @brief Convert parameter array to an universal form
 297          * @param array $args Parameter array
 298          * @return array universalized parameter array
 299          */
 300         private static function getParam($args) {
 301                 unset($args[0]);
 302
 303                 // When the second function parameter is an array then use this as the parameter array
 304                 if ((count($args) > 0) && (is_array($args[1]))) {
 305                         return $args[1];
 306                 } else {
 307                         return $args;
 308                 }
 309         }
 310
 311         /**
 312          * @brief Executes a prepared statement that returns data
 313          * @usage Example: $r = p("SELECT * FROM `item` WHERE `guid` = ?", $guid);
 314          *
 315          * Please only use it with complicated queries.
 316          * For all regular queries please use dba::select or dba::exists
 317          *
 318          * @param string $sql SQL statement
 319          * @return bool|object statement object
 320          */
 321         public static function p($sql) {
 322                 $a = get_app();
 323
 324                 $stamp1 = microtime(true);
 325
 326                 $params = self::getParam(func_get_args());
 327
 328                 // Renumber the array keys to be sure that they fit
 329                 $i = 0;
 330                 $args = [];
 331                 foreach ($params AS $param) {
 332                         // Avoid problems with some MySQL servers and boolean values. See issue #3645
 333                         if (is_bool($param)) {
 334                                 $param = (int)$param;
 335                         }
 336                         $args[++$i] = $param;
 337                 }
 338
 339                 if (!self::$connected) {
 340                         return false;
 341                 }
 342
 343                 if ((substr_count($sql, '?') != count($args)) && (count($args) > 0)) {
 344                         // Question: Should we continue or stop the query here?
 345                         logger('Parameter mismatch. Query "'.$sql.'" - Parameters '.print_r($args, true), LOGGER_DEBUG);
 346                 }
 347
 348                 $sql = self::clean_query($sql);
 349                 $sql = self::any_value_fallback($sql);
 350
 351                 $orig_sql = $sql;
 352
 353                 if (x($a->config,'system') && x($a->config['system'], 'db_callstack')) {
 354                         $sql = "/*".System::callstack()." */ ".$sql;
 355                 }
 356
 357                 self::$error = '';
 358                 self::$errorno = 0;
 359                 self::$affected_rows = 0;
 360
 361                 // We have to make some things different if this function is called from "e"
 362                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
 363
 364                 if (isset($trace[1])) {
 365                         $called_from = $trace[1];
 366                 } else {
 367                         // We use just something that is defined to avoid warnings
 368                         $called_from = $trace[0];
 369                 }
 370                 // We are having an own error logging in the function "e"
 371                 $called_from_e = ($called_from['function'] == 'e');
 372
 373                 switch (self::$driver) {
 374                         case 'pdo':
 375                                 // If there are no arguments we use "query"
 376                                 if (count($args) == 0) {
 377                                         if (!$retval = self::$db->query($sql)) {
 378                                                 $errorInfo = self::$db->errorInfo();
 379                                                 self::$error = $errorInfo[2];
 380                                                 self::$errorno = $errorInfo[1];
 381                                                 $retval = false;
 382                                                 break;
 383                                         }
 384                                         self::$affected_rows = $retval->rowCount();
 385                                         break;
 386                                 }
 387
 388                                 if (!$stmt = self::$db->prepare($sql)) {
 389                                         $errorInfo = self::$db->errorInfo();
 390                                         self::$error = $errorInfo[2];
 391                                         self::$errorno = $errorInfo[1];
 392                                         $retval = false;
 393                                         break;
 394                                 }
 395
 396                                 foreach ($args AS $param => $value) {
 397                                         $stmt->bindParam($param, $args[$param]);
 398                                 }
 399
 400                                 if (!$stmt->execute()) {
 401                                         $errorInfo = $stmt->errorInfo();
 402                                         self::$error = $errorInfo[2];
 403                                         self::$errorno = $errorInfo[1];
 404                                         $retval = false;
 405                                 } else {
 406                                         $retval = $stmt;
 407                                         self::$affected_rows = $retval->rowCount();
 408                                 }
 409                                 break;
 410                         case 'mysqli':
 411                                 // There are SQL statements that cannot be executed with a prepared statement
 412                                 $parts = explode(' ', $orig_sql);
 413                                 $command = strtolower($parts[0]);
 414                                 $can_be_prepared = in_array($command, ['select', 'update', 'insert', 'delete']);
 415
 416                                 // The fallback routine is called as well when there are no arguments
 417                                 if (!$can_be_prepared || (count($args) == 0)) {
 418                                         $retval = self::$db->query(self::replace_parameters($sql, $args));
 419                                         if (self::$db->errno) {
 420                                                 self::$error = self::$db->error;
 421                                                 self::$errorno = self::$db->errno;
 422                                                 $retval = false;
 423                                         } else {
 424                                                 if (isset($retval->num_rows)) {
 425                                                         self::$affected_rows = $retval->num_rows;
 426                                                 } else {
 427                                                         self::$affected_rows = self::$db->affected_rows;
 428                                                 }
 429                                         }
 430                                         break;
 431                                 }
 432
 433                                 $stmt = self::$db->stmt_init();
 434
 435                                 if (!$stmt->prepare($sql)) {
 436                                         self::$error = $stmt->error;
 437                                         self::$errorno = $stmt->errno;
 438                                         $retval = false;
 439                                         break;
 440                                 }
 441
 442                                 $params = '';
 443                                 $values = [];
 444                                 foreach ($args AS $param => $value) {
 445                                         if (is_int($args[$param])) {
 446                                                 $params .= 'i';
 447                                         } elseif (is_float($args[$param])) {
 448                                                 $params .= 'd';
 449                                         } elseif (is_string($args[$param])) {
 450                                                 $params .= 's';
 451                                         } else {
 452                                                 $params .= 'b';
 453                                         }
 454                                         $values[] = &$args[$param];
 455                                 }
 456
 457                                 if (count($values) > 0) {
 458                                         array_unshift($values, $params);
 459                                         call_user_func_array([$stmt, 'bind_param'], $values);
 460                                 }
 461
 462                                 if (!$stmt->execute()) {
 463                                         self::$error = self::$db->error;
 464                                         self::$errorno = self::$db->errno;
 465                                         $retval = false;
 466                                 } else {
 467                                         $stmt->store_result();
 468                                         $retval = $stmt;
 469                                         self::$affected_rows = $retval->affected_rows;
 470                                 }
 471                                 break;
 472                 }
 473
 474                 // We are having an own error logging in the function "e"
 475                 if ((self::$errorno != 0) && !$called_from_e) {
 476                         // We have to preserve the error code, somewhere in the logging it get lost
 477                         $error = self::$error;
 478                         $errorno = self::$errorno;
 479
 480                         logger('DB Error '.self::$errorno.': '.self::$error."\n".
 481                                 System::callstack(8)."\n".self::replace_parameters($sql, $params));
 482
 483                         self::$error = $error;
 484                         self::$errorno = $errorno;
 485                 }
 486
 487                 $a->save_timestamp($stamp1, 'database');
 488
 489                 if (x($a->config,'system') && x($a->config['system'], 'db_log')) {
 490
 491                         $stamp2 = microtime(true);
 492                         $duration = (float)($stamp2 - $stamp1);
 493
 494                         if (($duration > $a->config["system"]["db_loglimit"])) {
 495                                 $duration = round($duration, 3);
 496                                 $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 497
 498                                 @file_put_contents($a->config["system"]["db_log"], Temporal::utcNow()."\t".$duration."\t".
 499                                                 basename($backtrace[1]["file"])."\t".
 500                                                 $backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
 501                                                 substr(self::replace_parameters($sql, $args), 0, 2000)."\n", FILE_APPEND);
 502                         }
 503                 }
 504                 return $retval;
 505         }
 506
 507         /**
 508          * @brief Executes a prepared statement like UPDATE or INSERT that doesn't return data
 509          *
 510          * Please use dba::delete, dba::insert, dba::update, ... instead
 511          *
 512          * @param string $sql SQL statement
 513          * @return boolean Was the query successfull? False is returned only if an error occurred
 514          */
 515         public static function e($sql) {
 516                 $a = get_app();
 517
 518                 $stamp = microtime(true);
 519
 520                 $params = self::getParam(func_get_args());
 521
 522                 // In a case of a deadlock we are repeating the query 20 times
 523                 $timeout = 20;
 524
 525                 do {
 526                         $stmt = self::p($sql, $params);
 527
 528                         if (is_bool($stmt)) {
 529                                 $retval = $stmt;
 530                         } elseif (is_object($stmt)) {
 531                                 $retval = true;
 532                         } else {
 533                                 $retval = false;
 534                         }
 535
 536                         self::close($stmt);
 537
 538                 } while ((self::$errorno == 1213) && (--$timeout > 0));
 539
 540                 if (self::$errorno != 0) {
 541                         // We have to preserve the error code, somewhere in the logging it get lost
 542                         $error = self::$error;
 543                         $errorno = self::$errorno;
 544
 545                         logger('DB Error '.self::$errorno.': '.self::$error."\n".
 546                                 System::callstack(8)."\n".self::replace_parameters($sql, $params));
 547
 548                         self::$error = $error;
 549                         self::$errorno = $errorno;
 550                 }
 551
 552                 $a->save_timestamp($stamp, "database_write");
 553
 554                 return $retval;
 555         }
 556
 557         /**
 558          * @brief Check if data exists
 559          *
 560          * @param string $table Table name
 561          * @param array $condition array of fields for condition
 562          *
 563          * @return boolean Are there rows for that condition?
 564          */
 565         public static function exists($table, $condition) {
 566                 if (empty($table)) {
 567                         return false;
 568                 }
 569
 570                 $fields = [];
 571
 572                 $array_element = each($condition);
 573                 $array_key = $array_element['key'];
 574                 if (!is_int($array_key)) {
 575                         $fields = [$array_key];
 576                 }
 577
 578                 $stmt = self::select($table, $fields, $condition, ['limit' => 1]);
 579
 580                 if (is_bool($stmt)) {
 581                         $retval = $stmt;
 582                 } else {
 583                         $retval = (self::num_rows($stmt) > 0);
 584                 }
 585
 586                 self::close($stmt);
 587
 588                 return $retval;
 589         }
 590
 591         /**
 592          * Fetches the first row
 593          *
 594          * Please use dba::selectFirst or dba::exists whenever this is possible.
 595          *
 596          * @brief Fetches the first row
 597          * @param string $sql SQL statement
 598          * @return array first row of query
 599          */
 600         public static function fetch_first($sql) {
 601                 $params = self::getParam(func_get_args());
 602
 603                 $stmt = self::p($sql, $params);
 604
 605                 if (is_bool($stmt)) {
 606                         $retval = $stmt;
 607                 } else {
 608                         $retval = self::fetch($stmt);
 609                 }
 610
 611                 self::close($stmt);
 612
 613                 return $retval;
 614         }
 615
 616         /**
 617          * @brief Returns the number of affected rows of the last statement
 618          *
 619          * @return int Number of rows
 620          */
 621         public static function affected_rows() {
 622                 return self::$affected_rows;
 623         }
 624
 625         /**
 626          * @brief Returns the number of columns of a statement
 627          *
 628          * @param object Statement object
 629          * @return int Number of columns
 630          */
 631         public static function columnCount($stmt) {
 632                 if (!is_object($stmt)) {
 633                         return 0;
 634                 }
 635                 switch (self::$driver) {
 636                         case 'pdo':
 637                                 return $stmt->columnCount();
 638                         case 'mysqli':
 639                                 return $stmt->field_count;
 640                 }
 641                 return 0;
 642         }
 643         /**
 644          * @brief Returns the number of rows of a statement
 645          *
 646          * @param PDOStatement|mysqli_result|mysqli_stmt Statement object
 647          * @return int Number of rows
 648          */
 649         public static function num_rows($stmt) {
 650                 if (!is_object($stmt)) {
 651                         return 0;
 652                 }
 653                 switch (self::$driver) {
 654                         case 'pdo':
 655                                 return $stmt->rowCount();
 656                         case 'mysqli':
 657                                 return $stmt->num_rows;
 658                 }
 659                 return 0;
 660         }
 661
 662         /**
 663          * @brief Fetch a single row
 664          *
 665          * @param mixed $stmt statement object
 666          * @return array current row
 667          */
 668         public static function fetch($stmt) {
 669                 if (!is_object($stmt)) {
 670                         return false;
 671                 }
 672
 673                 switch (self::$driver) {
 674                         case 'pdo':
 675                                 return $stmt->fetch(PDO::FETCH_ASSOC);
 676                         case 'mysqli':
 677                                 if (get_class($stmt) == 'mysqli_result') {
 678                                         return $stmt->fetch_assoc();
 679                                 }
 680
 681                                 // This code works, but is slow
 682
 683                                 // Bind the result to a result array
 684                                 $cols = [];
 685
 686                                 $cols_num = [];
 687                                 for ($x = 0; $x < $stmt->field_count; $x++) {
 688                                         $cols[] = &$cols_num[$x];
 689                                 }
 690
 691                                 call_user_func_array([$stmt, 'bind_result'], $cols);
 692
 693                                 if (!$stmt->fetch()) {
 694                                         return false;
 695                                 }
 696
 697                                 // The slow part:
 698                                 // We need to get the field names for the array keys
 699                                 // It seems that there is no better way to do this.
 700                                 $result = $stmt->result_metadata();
 701                                 $fields = $result->fetch_fields();
 702
 703                                 $columns = [];
 704                                 foreach ($cols_num AS $param => $col) {
 705                                         $columns[$fields[$param]->name] = $col;
 706                                 }
 707                                 return $columns;
 708                 }
 709         }
 710
 711         /**
 712          * @brief Insert a row into a table
 713          *
 714          * @param string $table Table name
 715          * @param array $param parameter array
 716          * @param bool $on_duplicate_update Do an update on a duplicate entry
 717          *
 718          * @return boolean was the insert successfull?
 719          */
 720         public static function insert($table, $param, $on_duplicate_update = false) {
 721
 722                 if (empty($table) || empty($param)) {
 723                         logger('Table and fields have to be set');
 724                         return false;
 725                 }
 726
 727                 $sql = "INSERT INTO `".self::escape($table)."` (`".implode("`, `", array_keys($param))."`) VALUES (".
 728                         substr(str_repeat("?, ", count($param)), 0, -2).")";
 729
 730                 if ($on_duplicate_update) {
 731                         $sql .= " ON DUPLICATE KEY UPDATE `".implode("` = ?, `", array_keys($param))."` = ?";
 732
 733                         $values = array_values($param);
 734                         $param = array_merge_recursive($values, $values);
 735                 }
 736
 737                 return self::e($sql, $param);
 738         }
 739
 740         /**
 741          * @brief Fetch the id of the last insert command
 742          *
 743          * @return integer Last inserted id
 744          */
 745         public static function lastInsertId() {
 746                 switch (self::$driver) {
 747                         case 'pdo':
 748                                 $id = self::$db->lastInsertId();
 749                                 break;
 750                         case 'mysqli':
 751                                 $id = self::$db->insert_id;
 752                                 break;
 753                 }
 754                 return $id;
 755         }
 756
 757         /**
 758          * @brief Locks a table for exclusive write access
 759          *
 760          * This function can be extended in the future to accept a table array as well.
 761          *
 762          * @param string $table Table name
 763          *
 764          * @return boolean was the lock successful?
 765          */
 766         public static function lock($table) {
 767                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 768                 self::e("SET autocommit=0");
 769                 $success = self::e("LOCK TABLES `".self::escape($table)."` WRITE");
 770                 if (!$success) {
 771                         self::e("SET autocommit=1");
 772                 } else {
 773                         self::$in_transaction = true;
 774                 }
 775                 return $success;
 776         }
 777
 778         /**
 779          * @brief Unlocks all locked tables
 780          *
 781          * @return boolean was the unlock successful?
 782          */
 783         public static function unlock() {
 784                 // See here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
 785                 self::e("COMMIT");
 786                 $success = self::e("UNLOCK TABLES");
 787                 self::e("SET autocommit=1");
 788                 self::$in_transaction = false;
 789                 return $success;
 790         }
 791
 792         /**
 793          * @brief Starts a transaction
 794          *
 795          * @return boolean Was the command executed successfully?
 796          */
 797         public static function transaction() {
 798                 if (!self::e('COMMIT')) {
 799                         return false;
 800                 }
 801                 if (!self::e('START TRANSACTION')) {
 802                         return false;
 803                 }
 804                 self::$in_transaction = true;
 805                 return true;
 806         }
 807
 808         /**
 809          * @brief Does a commit
 810          *
 811          * @return boolean Was the command executed successfully?
 812          */
 813         public static function commit() {
 814                 if (!self::e('COMMIT')) {
 815                         return false;
 816                 }
 817                 self::$in_transaction = false;
 818                 return true;
 819         }
 820
 821         /**
 822          * @brief Does a rollback
 823          *
 824          * @return boolean Was the command executed successfully?
 825          */
 826         public static function rollback() {
 827                 if (!self::e('ROLLBACK')) {
 828                         return false;
 829                 }
 830                 self::$in_transaction = false;
 831                 return true;
 832         }
 833
 834         /**
 835          * @brief Build the array with the table relations
 836          *
 837          * The array is build from the database definitions in DBStructure.php
 838          *
 839          * This process must only be started once, since the value is cached.
 840          */
 841         private static function build_relation_data() {
 842                 $definition = DBStructure::definition();
 843
 844                 foreach ($definition AS $table => $structure) {
 845                         foreach ($structure['fields'] AS $field => $field_struct) {
 846                                 if (isset($field_struct['relation'])) {
 847                                         foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
 848                                                 self::$relation[$rel_table][$rel_field][$table][] = $field;
 849                                         }
 850                                 }
 851                         }
 852                 }
 853         }
 854
 855         /**
 856          * @brief Delete a row from a table
 857          *
 858          * @param string  $table       Table name
 859          * @param array   $conditions  Field condition(s)
 860          * @param boolean $in_process  Internal use: Only do a commit after the last delete
 861          * @param array   $callstack   Internal use: prevent endless loops
 862          *
 863          * @return boolean|array was the delete successful? When $in_process is set: deletion data
 864          */
 865         public static function delete($table, array $conditions, $in_process = false, array &$callstack = [])
 866         {
 867                 if (empty($table) || empty($conditions)) {
 868                         logger('Table and conditions have to be set');
 869                         return false;
 870                 }
 871
 872                 $commands = [];
 873
 874                 // Create a key for the loop prevention
 875                 $key = $table . ':' . implode(':', array_keys($conditions)) . ':' . implode(':', $conditions);
 876
 877                 // We quit when this key already exists in the callstack.
 878                 if (isset($callstack[$key])) {
 879                         return $commands;
 880                 }
 881
 882                 $callstack[$key] = true;
 883
 884                 $table = self::escape($table);
 885
 886                 $commands[$key] = ['table' => $table, 'conditions' => $conditions];
 887
 888                 // To speed up the whole process we cache the table relations
 889                 if (count(self::$relation) == 0) {
 890                         self::build_relation_data();
 891                 }
 892
 893                 // Is there a relation entry for the table?
 894                 if (isset(self::$relation[$table])) {
 895                         // We only allow a simple "one field" relation.
 896                         $field = array_keys(self::$relation[$table])[0];
 897                         $rel_def = array_values(self::$relation[$table])[0];
 898
 899                         // Create a key for preventing double queries
 900                         $qkey = $field . '-' . $table . ':' . implode(':', array_keys($conditions)) . ':' . implode(':', $conditions);
 901
 902                         // When the search field is the relation field, we don't need to fetch the rows
 903                         // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
 904                         if ((count($conditions) == 1) && ($field == array_keys($conditions)[0])) {
 905                                 foreach ($rel_def AS $rel_table => $rel_fields) {
 906                                         foreach ($rel_fields AS $rel_field) {
 907                                                 $retval = self::delete($rel_table, [$rel_field => array_values($conditions)[0]], true, $callstack);
 908                                                 $commands = array_merge($commands, $retval);
 909                                         }
 910                                 }
 911                                 // We quit when this key already exists in the callstack.
 912                         } elseif (!isset($callstack[$qkey])) {
 913
 914                                 $callstack[$qkey] = true;
 915
 916                                 // Fetch all rows that are to be deleted
 917                                 $data = self::select($table, [$field], $conditions);
 918
 919                                 while ($row = self::fetch($data)) {
 920                                         // Now we accumulate the delete commands
 921                                         $retval = self::delete($table, [$field => $row[$field]], true, $callstack);
 922                                         $commands = array_merge($commands, $retval);
 923                                 }
 924
 925                                 self::close($data);
 926
 927                                 // Since we had split the delete command we don't need the original command anymore
 928                                 unset($commands[$key]);
 929                         }
 930                 }
 931
 932                 if (!$in_process) {
 933                         // Now we finalize the process
 934                         $do_transaction = !self::$in_transaction;
 935
 936                         if ($do_transaction) {
 937                                 self::transaction();
 938                         }
 939
 940                         $compacted = [];
 941                         $counter = [];
 942
 943                         foreach ($commands AS $command) {
 944                                 $conditions = $command['conditions'];
 945                                 $array_element = each($conditions);
 946                                 $array_key = $array_element['key'];
 947                                 if (is_int($array_key)) {
 948                                         $condition_string = " WHERE " . array_shift($conditions);
 949                                 } else {
 950                                         $condition_string = " WHERE `" . implode("` = ? AND `", array_keys($conditions)) . "` = ?";
 951                                 }
 952
 953                                 if ((count($command['conditions']) > 1) || is_int($array_key)) {
 954                                         $sql = "DELETE FROM `" . $command['table'] . "`" . $condition_string;
 955                                         logger(self::replace_parameters($sql, $conditions), LOGGER_DATA);
 956
 957                                         if (!self::e($sql, $conditions)) {
 958                                                 if ($do_transaction) {
 959                                                         self::rollback();
 960                                                 }
 961                                                 return false;
 962                                         }
 963                                 } else {
 964                                         $key_table = $command['table'];
 965                                         $key_condition = array_keys($command['conditions'])[0];
 966                                         $value = array_values($command['conditions'])[0];
 967
 968                                         // Split the SQL queries in chunks of 100 values
 969                                         // We do the $i stuff here to make the code better readable
 970                                         $i = $counter[$key_table][$key_condition];
 971                                         if (count($compacted[$key_table][$key_condition][$i]) > 100) {
 972                                                 ++$i;
 973                                         }
 974
 975                                         $compacted[$key_table][$key_condition][$i][$value] = $value;
 976                                         $counter[$key_table][$key_condition] = $i;
 977                                 }
 978                         }
 979                         foreach ($compacted AS $table => $values) {
 980                                 foreach ($values AS $field => $field_value_list) {
 981                                         foreach ($field_value_list AS $field_values) {
 982                                                 $sql = "DELETE FROM `" . $table . "` WHERE `" . $field . "` IN (" .
 983                                                         substr(str_repeat("?, ", count($field_values)), 0, -2) . ");";
 984
 985                                                 logger(self::replace_parameters($sql, $field_values), LOGGER_DATA);
 986
 987                                                 if (!self::e($sql, $field_values)) {
 988                                                         if ($do_transaction) {
 989                                                                 self::rollback();
 990                                                         }
 991                                                         return false;
 992                                                 }
 993                                         }
 994                                 }
 995                         }
 996                         if ($do_transaction) {
 997                                 self::commit();
 998                         }
 999                         return true;
1000                 }
1001
1002                 return $commands;
1003         }
1004
1005         /**
1006          * @brief Updates rows
1007          *
1008          * Updates rows in the database. When $old_fields is set to an array,
1009          * the system will only do an update if the fields in that array changed.
1010          *
1011          * Attention:
1012          * Only the values in $old_fields are compared.
1013          * This is an intentional behaviour.
1014          *
1015          * Example:
1016          * We include the timestamp field in $fields but not in $old_fields.
1017          * Then the row will only get the new timestamp when the other fields had changed.
1018          *
1019          * When $old_fields is set to a boolean value the system will do this compare itself.
1020          * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
1021          *
1022          * Attention:
1023          * Only set $old_fields to a boolean value when you are sure that you will update a single row.
1024          * When you set $old_fields to "true" then $fields must contain all relevant fields!
1025          *
1026          * @param string $table Table name
1027          * @param array $fields contains the fields that are updated
1028          * @param array $condition condition array with the key values
1029          * @param array|boolean $old_fields array with the old field values that are about to be replaced (true = update on duplicate)
1030          *
1031          * @return boolean was the update successfull?
1032          */
1033         public static function update($table, $fields, $condition, $old_fields = []) {
1034
1035                 if (empty($table) || empty($fields) || empty($condition)) {
1036                         logger('Table, fields and condition have to be set');
1037                         return false;
1038                 }
1039
1040                 $table = self::escape($table);
1041
1042                 $array_element = each($condition);
1043                 $array_key = $array_element['key'];
1044                 if (is_int($array_key)) {
1045                         $condition_string = " WHERE ".array_shift($condition);
1046                 } else {
1047                         $condition_string = " WHERE `".implode("` = ? AND `", array_keys($condition))."` = ?";
1048                 }
1049
1050                 if (is_bool($old_fields)) {
1051                         $do_insert = $old_fields;
1052
1053                         $old_fields = self::selectFirst($table, [], $condition);
1054
1055                         if (is_bool($old_fields)) {
1056                                 if ($do_insert) {
1057                                         $values = array_merge($condition, $fields);
1058                                         return self::insert($table, $values, $do_insert);
1059                                 }
1060                                 $old_fields = [];
1061                         }
1062                 }
1063
1064                 $do_update = (count($old_fields) == 0);
1065
1066                 foreach ($old_fields AS $fieldname => $content) {
1067                         if (isset($fields[$fieldname])) {
1068                                 if ($fields[$fieldname] == $content) {
1069                                         unset($fields[$fieldname]);
1070                                 } else {
1071                                         $do_update = true;
1072                                 }
1073                         }
1074                 }
1075
1076                 if (!$do_update || (count($fields) == 0)) {
1077                         return true;
1078                 }
1079
1080                 $sql = "UPDATE `".$table."` SET `".
1081                         implode("` = ?, `", array_keys($fields))."` = ?".$condition_string;
1082
1083                 $params1 = array_values($fields);
1084                 $params2 = array_values($condition);
1085                 $params = array_merge_recursive($params1, $params2);
1086
1087                 return self::e($sql, $params);
1088         }
1089
1090         /**
1091          * Retrieve a single record from a table and returns it in an associative array
1092          *
1093          * @brief Retrieve a single record from a table
1094          * @param string $table
1095          * @param array  $fields
1096          * @param array  $condition
1097          * @param array  $params
1098          * @return bool|array
1099          * @see dba::select
1100          */
1101         public static function selectFirst($table, array $fields = [], array $condition = [], $params = [])
1102         {
1103                 $params['limit'] = 1;
1104                 $result = self::select($table, $fields, $condition, $params);
1105
1106                 if (is_bool($result)) {
1107                         return $result;
1108                 } else {
1109                         $row = self::fetch($result);
1110                         self::close($result);
1111                         return $row;
1112                 }
1113         }
1114
1115         /**
1116          * @brief Select rows from a table
1117          *
1118          * @param string $table     Table name
1119          * @param array  $fields    Array of selected fields, empty for all
1120          * @param array  $condition Array of fields for condition
1121          * @param array  $params    Array of several parameters
1122          *
1123          * @return boolean|object
1124          *
1125          * Example:
1126          * $table = "item";
1127          * $fields = array("id", "uri", "uid", "network");
1128          *
1129          * $condition = array("uid" => 1, "network" => 'dspr');
1130          * or:
1131          * $condition = array("`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr');
1132          *
1133          * $params = array("order" => array("id", "received" => true), "limit" => 10);
1134          *
1135          * $data = dba::select($table, $fields, $condition, $params);
1136          */
1137         public static function select($table, array $fields = [], array $condition = [], array $params = [])
1138         {
1139                 if ($table == '') {
1140                         return false;
1141                 }
1142
1143                 if (count($fields) > 0) {
1144                         $select_fields = "`" . implode("`, `", array_values($fields)) . "`";
1145                 } else {
1146                         $select_fields = "*";
1147                 }
1148
1149                 $condition_string = self::buildCondition($condition);
1150
1151                 $order_string = '';
1152                 if (isset($params['order'])) {
1153                         $order_string = " ORDER BY ";
1154                         foreach ($params['order'] AS $fields => $order) {
1155                                 if (!is_int($fields)) {
1156                                         $order_string .= "`" . $fields . "` " . ($order ? "DESC" : "ASC") . ", ";
1157                                 } else {
1158                                         $order_string .= "`" . $order . "`, ";
1159                                 }
1160                         }
1161                         $order_string = substr($order_string, 0, -2);
1162                 }
1163
1164                 $limit_string = '';
1165                 if (isset($params['limit']) && is_int($params['limit'])) {
1166                         $limit_string = " LIMIT " . $params['limit'];
1167                 }
1168
1169                 if (isset($params['limit']) && is_array($params['limit'])) {
1170                         $limit_string = " LIMIT " . intval($params['limit'][0]) . ", " . intval($params['limit'][1]);
1171                 }
1172
1173                 $sql = "SELECT " . $select_fields . " FROM `" . $table . "`" . $condition_string . $order_string . $limit_string;
1174
1175                 $result = self::p($sql, $condition);
1176
1177                 return $result;
1178         }
1179
1180         /**
1181          * @brief Counts the rows from a table satisfying the provided condition
1182          *
1183          * @param string $table Table name
1184          * @param array $condition array of fields for condition
1185          *
1186          * @return int
1187          *
1188          * Example:
1189          * $table = "item";
1190          *
1191          * $condition = ["uid" => 1, "network" => 'dspr'];
1192          * or:
1193          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1194          *
1195          * $count = dba::count($table, $condition);
1196          */
1197         public static function count($table, array $condition = [])
1198         {
1199                 if ($table == '') {
1200                         return false;
1201                 }
1202
1203                 $condition_string = self::buildCondition($condition);
1204
1205                 $sql = "SELECT COUNT(*) AS `count` FROM `".$table."`".$condition_string;
1206
1207                 $row = self::fetch_first($sql, $condition);
1208
1209                 return $row['count'];
1210         }
1211
1212         /**
1213          * @brief Returns the SQL condition string built from the provided condition array
1214          *
1215          * This function operates with two modes.
1216          * - Supplied with a filed/value associative array, it builds simple strict
1217          *   equality conditions linked by AND.
1218          * - Supplied with a flat list, the first element is the condition string and
1219          *   the following arguments are the values to be interpolated
1220          *
1221          * $condition = ["uid" => 1, "network" => 'dspr'];
1222          * or:
1223          * $condition = ["`uid` = ? AND `network` IN (?, ?)", 1, 'dfrn', 'dspr'];
1224          *
1225          * In either case, the provided array is left with the parameters only
1226          *
1227          * @param array $condition
1228          * @return string
1229          */
1230         private static function buildCondition(array &$condition = [])
1231         {
1232                 $condition_string = '';
1233                 if (count($condition) > 0) {
1234                         $array_element = each($condition);
1235                         $array_key = $array_element['key'];
1236                         if (is_int($array_key)) {
1237                                 $condition_string = " WHERE ".array_shift($condition);
1238                         } else {
1239                                 $condition_string = " WHERE `".implode("` = ? AND `", array_keys($condition))."` = ?";
1240                         }
1241                 }
1242
1243                 return $condition_string;
1244         }
1245
1246         /**
1247          * @brief Fills an array with data from a query
1248          *
1249          * @param object $stmt statement object
1250          * @return array Data array
1251          */
1252         public static function inArray($stmt, $do_close = true) {
1253                 if (is_bool($stmt)) {
1254                         return $stmt;
1255                 }
1256
1257                 $data = [];
1258                 while ($row = self::fetch($stmt)) {
1259                         $data[] = $row;
1260                 }
1261                 if ($do_close) {
1262                         self::close($stmt);
1263                 }
1264                 return $data;
1265         }
1266
1267         /**
1268          * @brief Returns the error number of the last query
1269          *
1270          * @return string Error number (0 if no error)
1271          */
1272         public static function errorNo() {
1273                 return self::$errorno;
1274         }
1275
1276         /**
1277          * @brief Returns the error message of the last query
1278          *
1279          * @return string Error message ('' if no error)
1280          */
1281         public static function errorMessage() {
1282                 return self::$error;
1283         }
1284
1285         /**
1286          * @brief Closes the current statement
1287          *
1288          * @param object $stmt statement object
1289          * @return boolean was the close successful?
1290          */
1291         public static function close($stmt) {
1292                 if (!is_object($stmt)) {
1293                         return false;
1294                 }
1295
1296                 switch (self::$driver) {
1297                         case 'pdo':
1298                                 return $stmt->closeCursor();
1299                         case 'mysqli':
1300                                 $stmt->free_result();
1301                                 return $stmt->close();
1302                 }
1303         }
1304 }
1305
1306 function dbesc($str) {
1307         if (dba::$connected) {
1308                 return(dba::escape($str));
1309         } else {
1310                 return(str_replace("'","\\'",$str));
1311         }
1312 }
1313
1314 /**
1315  * @brief execute SQL query with printf style args - deprecated
1316  *
1317  * Please use the dba:: functions instead:
1318  * dba::select, dba::exists, dba::insert
1319  * dba::delete, dba::update, dba::p, dba::e
1320  *
1321  * @param $args Query parameters (1 to N parameters of different types)
1322  * @return array|bool Query array
1323  */
1324 function q($sql) {
1325         $args = func_get_args();
1326         unset($args[0]);
1327
1328         if (!dba::$connected) {
1329                 return false;
1330         }
1331
1332         $sql = dba::clean_query($sql);
1333         $sql = dba::any_value_fallback($sql);
1334
1335         $stmt = @vsprintf($sql, $args);
1336
1337         $ret = dba::p($stmt);
1338
1339         if (is_bool($ret)) {
1340                 return $ret;
1341         }
1342
1343         $columns = dba::columnCount($ret);
1344
1345         $data = dba::inArray($ret);
1346
1347         if ((count($data) == 0) && ($columns == 0)) {
1348                 return true;
1349         }
1350
1351         return $data;
1352 }
1353
1354 function dba_timer() {
1355         return microtime(true);
1356 }